This is in preparation for the addition of --harmony-destructuring-assignment.
BUG=v8:811
LOG=n
Review URL: https://codereview.chromium.org/1450193002
Cr-Commit-Position: refs/heads/master@{#32098}
This patch prohibits lexical bindings from being called 'let', even in
sloppy mode, following the ES2015 specification. The change affects
multiple cases of lexical bindings, including simple let/const declarations
and both kinds of for loops. var and legacy const bindings still permit
the name to be let, including in destructuring cases. Tests are added to
verify, though some cases are commented out since they led to (pre-existing)
crashes.
BUG=v8:4403
R=adamk
LOG=Y
Review URL: https://codereview.chromium.org/1371263003
Cr-Commit-Position: refs/heads/master@{#31115}
This patch makes 'let' a contextual keyword in both strict and sloppy mode.
It behaves as a keyword when used at the beginning of a StatementListItem
or lexical declaration at the beginning of a for statement, if it is followed
by an identifier, [ or {. Implementing this change requires an extra token
look-ahead by the parser which is only invoked in certain cases (so as to
avoid parsing RegExps as ECMAScript tokens). This might result in a slowdown
of the scanner, but performance testing of this patch hasn't yet found much
of a regression.
BUG=v8:3305
LOG=Y
R=adamk,vogelheim
Review URL: https://codereview.chromium.org/1315673009
Cr-Commit-Position: refs/heads/master@{#30451}
